Effects of nimodipine on EEG and 31P-NMR spectra during and after incomplete forebrain ischemia in the rat.

The effect of nimodipine was studied on EEG power density spectra as well as on 31P-NMR spectra of the brain before, during and after four-vessel occlusion (FVO) in the restrained conscious rat. EEG-spectral analysis: eight rats were submitted to 5 min FVO and four of them received nimodipine (1 mg/kg orally) 75 min before FVO. In the nimodipine-treated rats the post-ischemic overshoot of the EEG power density was significantly lower for the theta, alpha and beta band activity. 31P-NMR spectroscopy: the relative concentrations of phosphocreatine (PCr), ATP and Pi as well as intracellular pH were measured at different intervals after 10 min FVO (n = 10). All values normalised within 15-30 min after restoration of cerebral blood flow without significant differences between nimodipine-treated and control rats. It is concluded that pretreatment with nimodipine has a decreasing effect on the overshoot in EEG power density after transient incomplete forebrain ischemia. This effect was not correlated to significant changes in cerebral 'energy state', as measured by 31P-NMR spectroscopy.

Surgical management of acute subdural hematomas.

Acute subdural hematoma, local cerebral laceration and severe brain edema must be diagnosed at the earliest possible stage preferably by angiography and must be treated promptly by craniectomy of an adequate size in order to cope with all the blood clot, the lacerated brain tissue and the swollen brain.

Craniosynostosis: a new operative technique.

In the treatment of craniosynostosis several methods have been proposed to prevent craniectomies from early reclosure. New bone is formed at the edge of the craniectomy, but particularly at the outer surface of the dura. The author has developed a method to separate the edges from each other and to stop osteogenesis inside the craniectomy. The outer layer of the dura is dissected free from the inner layer folded over the edge of the groove and sutured to the outer periosteum. The operative technique and the results in 40 patients with a follow up of 17 years are described.

Maturation of a primitive neuroectodermal brain tumor? A case study with some remarks on the classification and nomenclature of 'primitive' CNS tumors.

A brain tumor in a 4-year-old child is described. The neoplasm was partly cystic and showed an a-typical multi-differentiated aspect. Microscopically the neoplasm had a clear-cut 'malignant' morphology. This tumor represents possibly a partly maturated primitive neuroectodermal brain tumor. The term PNET is briefly discussed in relation to the clinical implications.

Detachable balloon technique in the treatment of direct carotid-cavernous fistulas.

This paper describes the results obtained in the treatment of posttraumatic carotid-cavernous fistulas in 7 patients. The method used consisted of closure of the fistula with the aid of a detachable balloon. The advantage of this method over most others is that it closes the fistula but leaves carotid patency intact. In addition to the results, some technical aspects of this method are discussed.

[Direct arteriovenous fistula in the neck: one of the causes of tinnitus]. / Directe arterioveneuze fistels in de hals: een van de oorzaken van oorsuizen.

The most frequent symptom of an arteriovenous fistula is a bruit, often audible to the patient himself. The indication for treatment of such fistulae depends on the severity of the symptoms and on the risks of excessive strain on the heart, circulatory insufficiency and haemorrhages. The treatment of choice of direct communications between arteries and veins is detachable balloon occlusion by a transvascular technique rather than surgery. The method is described and three personal cases are reported. There were no complications, and the hospital stay was limited to 2-3 days.

[Craniosynostoses (17 years of experience with a new surgical technic)]. / Les craniosynostoses (17 ans d'expérience avec une nouvelle technique opératoire).

In the treatment of craniosynostosis methods have been proposed to prevent craniectomies from early reclosure. New bone is formed at the edge of the craniectomy but particularly at the outer surface of the dura. The author has developed a method to separate the edges from each other and to stop osteogenesis inside the craniectomy. The outer layer of the dura is dissected free from the inner layer, folded over the edge of the groove and sutured to the outer periosteum. The operative technique and the results in 40 patients with a follow up of up to 17 years are described.

[Vascular spasm and cerebral ischemia after meningeal hemorrhage caused by rupture of an aneurysm]. / Spasme vasculaire et ischémie cérébrale après hémorragie méningée par rupture anévrysmale.

The author discusses the epidemiology, the diagnosis, the clinical and morphological aspects of cerebral vasospasm from his personal experience and a study of the literature. Prediction and diagnosis of vasospasm is possible by evaluation of the amount of blood on CT scan, measuring fibrin breakdown products in the CSF and the findings of early EEG and Transcranial Doppler Sonography. CBF measurement is helpful in following the process of ischemia and deciding the right moment for operation. Early surgery on cerebral aneurysms is advocated in order to prevent rebleeding and for early removal of blood clot from the basal cisterns. If vasospasm and ischemia do develop, energetic treatment with hypervolemia and induced hypertension can be started without fear of rebleeding. Prophylactic intravenous administration of Nimodipine is thought to be of real value. Since the introduction of early surgery by the author 80 patients have been operated within 3 days after S.A.H. The mortality was 11% and the morbidity 7.5%. Management mortality and morbidity for the total group of 209 patients with S.A.H. treated either medically or surgically were 23.5% and 6% respectively. If one excludes the 18 patients that died within 24 hours the mortality was 15.6%.

[Intracranial reconstruction of the facial nerve in acoustic neurinoma surgery (author's transl)]. / La reconstruction intra-cranienne du nerf facial dans la chirurgie du neurinome de l'acoustique.

The authors have operated a consecutive series of 80 acoustic neurinomas. They were able to preserve the facial nerve in 53 patients. In thirteen cases an intracranial reconstruction of the nerve was performed : six times by direct anastomosis, in seven cases by grafting the nerve with the sural nerve. Details of the operative technique and the functional results are reported.

Facial nerve function after suboccipital removal of acoustic neurinoma.

The recovery of facial nerve function after suboccipital removal of 91 acoustic neurinomas is presented. The results after anatomical preservation of the nerve (60 cases), direct anastomosis of the nerve (7 cases), nerve grafting (16 cases), and facial hypoglossal anastomosis (8 cases) are presented after a follow-up period of 31.2 months. A simplified classification was used to describe motor function. The results are compared to those in the literature.

Growth of a prolactinoma during pregnancy. Case report and review.

A patient with hyperprolactinaemia and anovulation is described. Ovulation was induced with bromocriptine and the ensuing pregnancy caused rapid deterioration of vision and neurosurgical intervention. The management of hyperprolactinaemic infertility and the complications occurring during pregnancy in these patients are discussed.

Oligodendroglioma. A comparison of two grading systems.

In order to compare the grading system for oligodendrogliomas described by M.T. Smith (1983) with the conventional grading system according to Kernohan (1938), specimens from 72 patients were graded according to both systems, and survival times of the patients were compared. Survival rates decline in older patients. No interaction between the age of the patient and the degree of the tumor was found. No influence of localization of the tumor on survival was found. Similar to the system of Kernohan, the grading system of Smith distinguishes between only three groups of patients with significantly different survival times. In Smith's Grade A and Kernohan's Grade 1 the longest survivals are found; while in Smith's Grade D and Kernohan's Grade 4 the shortest survivals are found. Smith's Grades B and C as well as Kernohan's Grades 2 and 3 were intermediate with respect to the survival times of the patients and did not significantly differ from each other. With the independently significant features (cell density, pleomorphism, and necrosis) evaluated according to simple on-off scoring, and with the reduction from four grades to three, the grading system according to Smith would provide a simple and good, concise grading system for oligodendrogliomas of the brain.